If its a seam, just file it using a mill bastard file. If the rim is bulging out, take off the tire and using an adjustable wrench, grab the bulge with the wrench and bend it back as well as you can. Be sure to check both side of the rim, because the bulge is usually on both sides. If there is still a little blip left after you bend it back, file it down.
Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1